2x hAP AC Lite - Redundancy

Hi. I have 2x hAP AC Lite (RB952Ui-5ac2nD). WAN is connected into ETH1 in “Master hAP”. “Slave hAP” ETH1 is connected to ETH5 of “Master hAP”.
On “Master” is DHCP for LAN and WLAN (2,4+5GHz). I would like to set “Slave hAP” in other part of building as “redundant”. So it will offer same subnet on WLAN and LAN as Master.
What is the best way? WDS? Transparent bridge + CAPsMAN? And is there a way to do it “redundat”, so when “Master” will fall down, it will still offer at least local network (DHCP for LAN and WLAN with same leases)?